This EarthCache takes you on a tour, enjoyable in all seasons, through a natural glacial shaped valley located in Warden Woods along side the Taylor-Massey Creek. The valley's contour has been shaped by the erosion of Taylor-Massey Creek through the Halton glacial till plain (Toronto's last glacial deposit) and through several underlying glacial deposits. Here you will observe glacier formed cliffs, glacier placed erratics and you will be introduced to concepts of water and glacier erosion as well as watersheds and wetlands. At two points along the trail you will be asked to observe or answer questions. Please note the signs that indicate you are to stay on the paved trails. Please be mindful of the fragile ecosystems here that are being restored.
Erosion
Erosion is a geological process that shapes the landscape of the Earth, both on the surface and under water. It involves the breakdown of rock through either the individual or combined effects of wind, water, glacial movement and gravitational forces.
There are three main types of water erosion.
Abrasion is what a stream does to the sides of the bank, and to the material the bank is made of. The speed that abrasion occurs at in any stream is determined by its load. The load varies as it consists of material carried by the stream at any given time.
Solution is a chemical compound within the stream water that reacts chemically on the rocks or minerals that are in the banks subsurface.
Quarrying is the power of the water that grabs weakened areas from the bedrock or banks and starts to carry it down stream. Sometimes this action leaves an evident undercut in the bank.
Glaciers provide some of the most powerful erosion effects. They are most powerful transporters of sediment. There are multiple ways in which glaciers erode rock surfaces and formations. In one way, glaciers act like huge bulldozers, picking up anything from loose silt and sand to huge boulders – and pushing it along to be deposited elsewhere. Another way is like a file, literally scratching and scraping away at rock formations, leaving marks called striations in its path.
Watersheds and Wetlands
A watershed is a basin-like landform defined by highpoints and ridgelines that descend into lower elevations and stream valleys. A watershed carries water "shed" from the land after rain falls and snow melts. Water is channeled into soils, groundwaters, creeks, and streams, making its way to larger rivers and eventually larger bodies of water. Water is a universal solvent, affected by all that it comes in contact with including the land it goes through and the soils through which it travels. The important thing to understand about watersheds is what we do on the land affects water quality for all life living downstream. We all live near a watershed - any area that drains to a common waterway, such as a stream, lake, estuary, wetland, aquifer, or even the ocean is considered one.
A wetland is an area of land whose soil is saturated with moisture either permanently or seasonally. Such areas may also be covered partially or completely by shallow pools of water. Samples of wetlands include swamps, marshes, and bogs.
Wetlands are important elements of a watershed because they serve as the link between land and water resources.
Warden Woods EduTrail
You can enter Warden Woods from the southwest corner of Warden and St Clair Avenue and descend down the stairs and along the paved path to the posted co-ordinates. If you are biking there is a gentler paved trail head along St. Clair Avenue.
At the top of the stairs, at the posted co-ordinates you are standing above a flat new growth meadow. On the opposite bank of the Taylor-Massey Creek are high cliffs that were shaped by glaciers during the last ice age.
- Estimate the height of the cliff on the opposite bank from the water. You can use your elevation from the top of the trail at street level and compare it with the elevation at the bottom of the ravine as you walk along the trail.
As you head south you will come to the former location of an ox-bow, a U-shaped bend in a river or stream. At this point the Taylor-Massey Creek used to take a sharp turn away from the trail and toward another tall cliff, then turned back again. In an attempt to control the water flow and prevent erosion, the ox-bow has now been filled in by man, and limestone blocks placed along the bank to control the direction of the creek. The west side consists of a narrow clumping of coniferous trees with hardwoods towering along the elevated ridge on the west. On the east side are abundant groupings of maples, oaks and beeches.
Waypoint #2:
- From this location you will be able to see where the ox-bow was filled in. Over time as new growth takes root all signs of the oxbow will disappear. From this waypoint estimate the distance from the "new" west bank where the limestone blocks are in place, to the bottom of the steep cliff, the location of the former west bank of the Taylor-Massey Creek.
Waypoint # 3
- Using your knowledge of different types of stream erosion, identify the erosion types occuring along Taylor-Massey Creek at this location.
Wetlands are important to the watersheds we live in because they are part of a natural system that provides clean water, stores and slows down floodwaters, and protects shorelines from erosion and property damage. Wetlands are also habitats for wildlife that also provide opportunities for human recreation, such as birdwatching, hunting, fishing, and hiking.
Speaking of birdwatching, you are now in an area of Warden Woods that has one of the largest variety's of bird species in Toronto. Common in Warden Woods are chickadees, sparrows, ducks, and ovenbirds to orioles, scarlet tanagers, and hawks, as well as season warblers such as migrating Magnolia, Nashville, and Blackburnian. Many berry-bearing trees and shrubs help form a migratory songbird habitat within a large urbanized region. One of the best places to view birds can be found on the west side of Taylor-Massey Creek.
Logging Requirements
To claim a Found It log you are required to answer the questions above and E-mail them to me. Do not post your answers to your log. You may post any pictures you may have taken, but please DO NOT post SPOILER pictures. Answers are required within a reasonable amount of time.
References
City of Toronto, Parks, Forestry & Recreation | http://www.toronto.ca/parks
The Taylor Massey Project | http://thetmp.org